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1.
Int J Biol Macromol ; 263(Pt 2): 130381, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38395291

RESUMEN

Enzyme immobilization usually make use of nanomaterials to hold up biocatalysis stability in various unamiable reaction conditions, but also lead large discount on enzyme activity. Thus, there are abundant researches focus on how to deal with the relation of enzyme molecules and supports. In this work, a new state of highly active enzymes has been established through facile and novel in situ immobilization and soft template removal method to construct enzyme contained hollow silica nanosphere (catalase@HSN) biocatalysts where enzymes in the cavity exhibit "immobilized but not rigid state". The obtained catalase@HSN was characterized by transmission electron microscopy, scanning electron microscopy and confocal laser scanning microscopy et al. Catalase@HSN exhibits excellent activity (about 80 % activity recovery rate) and stability suffers from extreme pH, temperature, and organic solvents. Moreover, the reusability and storage stability of catalase@HSN also are satisfactory. This proposed strategy provides a facile method for preparing biocatalysts under mild conditions, facilitating the applications of immobilized enzyme in the fields of real biocatalytic industry with high apparent activity and passable stability.


Asunto(s)
Nanosferas , Dióxido de Silicio , Catalasa/metabolismo , Dióxido de Silicio/química , Nanosferas/química , Enzimas Inmovilizadas/química , Biocatálisis , Estabilidad de Enzimas
2.
Artículo en Inglés | MEDLINE | ID: mdl-35564554

RESUMEN

Vegetation restoration is considered a potentially useful strategy for controlling soil erosion and improving soil organic carbon (SOC) in arid and semiarid ecosystems. However, there is still debate regarding which vegetation restoration type is the best choice. In this study, four vegetation restoration types (i.e., grasslands, shrubs, forests and mixed forests) converted from sloping farmlands were selected to explore the SOC variation among the four types and to investigate which soil factors had the greatest effect on SOC. The results showed while the magnitude of effect differed between vegetation restoration type, all studied systems significantly increased SOC and labile organic carbon contents (p < 0.01), soil nutrients such as total nitrogen (TN) (p < 0.01), available nitrogen (AN) (p < 0.01), total phosphorus (TP) (p < 0.05) and available phosphorus (AP) (p < 0.05), soil enzyme activities such as phosphatase (p < 0.01), soil microbial biomass carbon (MBC) (p < 0.05), and basal respiration (BR) (p < 0.05), but had significant negative correlationswith polyphenol oxidase (p < 0.05). However, the effects of vegetation restoration of farmland converted to natural grasslands, shrubs, forests and mixed forests varied. Among the types studied, the mixed forests had the largest overall positive effects on SOC overall, followed by the natural grasslands. Soil nutrients such as N and P and soil microbial activities were the main factors that affected SOC after vegetation restoration. Mixed forests such as Robinia pseudoacacia and Caragana korshinskii are the best choice for farmland conversion on the central of the Loess Plateau.


Asunto(s)
Carbono , Suelo , Carbono/análisis , China , Ecosistema , Granjas , Bosques , Nitrógeno/análisis , Fósforo/análisis
3.
Mon Not R Astron Soc ; 477(3): 2886-2899, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30598558

RESUMEN

We contrast predictions for the high-redshift galaxy population and reionization history between cold dark matter (CDM) and an alternative self-interacting dark matter model based on the recently developed ETHOS framework that alleviates the small-scale CDM challenges within the Local Group. We perform the highest resolution hydrodynamical cosmological simulations (a 36 Mpc3 volume with gas cell mass of ∼ 105 M⊙ and minimum gas softening of ∼ 180 pc) within ETHOS to date - plus a CDM counterpart - to quantify the abundance of galaxies at high redshift and their impact on reionization. We find that ETHOS predicts galaxies with higher ultraviolet (UV) luminosities than their CDM counterparts and a faster build-up of the faint end of the UV luminosity function. These effects, however, make the optical depth to reionization less sensitive to the power spectrum cut-off: the ETHOS model differs from the CDM τ value by only 10 per cent and is consistent with Planck limits if the effective escape fraction of UV photons is 0.1-0.5. We conclude that current observations of high-redshift luminosity functions cannot differentiate between ETHOS and CDM models, but deep James Webb Space Telescope surveys of strongly lensed, inherently faint galaxies have the potential to test non-CDM models that offer attractive solutions to CDM's Local Group problems.

4.
Zhong Yao Cai ; 37(3): 379-83, 2014 Mar.
Artículo en Chino | MEDLINE | ID: mdl-25174098

RESUMEN

OBJECTIVE: To solve the problem that the single feed causing malnutrition, extension of the life cycle and low survival rates of Buthus martensii. METHODS: By using Minitab (R) 15.1.1.0.0., 7 different kinds of compound feed were designed, including minced meat mud (pork,chicken and rabbit), bran (fried yellow), sugar, milk, vegetable paste and multivitamin as raw material. RESULTS: Different proportions of compound feed that taking the yellow mealworm as main component had a significant effect on the growth, mortality and birth number of Buthus martensii. Compound feed 5 significantly reduced mortality of youth scorpion. The compound feed 4 was the best in improving the weight of scorpion larvae and youth scorpion, and the farrowing number of mother scorpion. Other indicators were also good. Proportions in meatmud (pork, chicken and rabbit), bran (fried yellow), sugar, milk, vegetable paste and multivitamin was 30.00%, 25.00%, 20.08%, 15.58%, 8.08% and 1.25%, respectively. CONCLUSION: The growth of Buthus martensii is significantly influenced by the type of feed. In the production of compound feed, the yellow mealworm with compound feed 4 can be popularized.


Asunto(s)
Alimentación Animal/análisis , Escorpiones , Aumento de Peso , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Carbohidratos , Proteínas en la Dieta , Insectos , Larva , Carne , Escorpiones/crecimiento & desarrollo
5.
Zhong Yao Cai ; 36(12): 1914-7, 2013 Dec.
Artículo en Chino | MEDLINE | ID: mdl-25090669

RESUMEN

OBJECTIVE: To study population dynamics of Buthus martensii and its wild spatial distribution pattern in Yan'an. METHODS: Every month, the 1st, 10th and 20th day were designated to collect Buthus martensii samples and count on the collection by using expansion pattern target, Taylor power law and Lwao m-x regression analysis. RESULTS: Taylor power law regression equation was Ig S2 = 1.6671 lg x + 0.1554; Lwao m-x regression equation was m = 1.3179 + 1.5133x. The spatial distribution pattern of Buthus martensii was negative binomial distribution and its population fluctuation curve in the wild presented a single peak. CONCLUSION: Spatial pattern of Buthus martensii in Yan'an is aggregated distribution which based on individual group, and the higher density,the greater aggregation degree.


Asunto(s)
Ecosistema , Escorpiones/crecimiento & desarrollo , Estaciones del Año , Animales , Conducta Animal/fisiología , China , Clima , Conservación de los Recursos Naturales , Matemática , Densidad de Población , Dinámica Poblacional , Escorpiones/fisiología
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